Joyce is a widowed former nurse living at the Coopers Chase retirement village. Initially appearing quiet and eager to please, she joins the Thursday Murder Club and discovers a newfound excitement for investigating real crimes. She carefully records the group's activities in her diary and frequently uses her unassuming, sweet demeanor to gather information without raising suspicion.

Elizabeth is the unofficial leader and co-founder of the Thursday Murder Club. She possesses a mysterious background involving extensive security connections, favors, and a deep understanding of investigative work. Sharp, resourceful, and highly organized, she assigns tasks to the group and is unafraid to manipulate police officers to gain access to restricted files.

Donna is a Police Constable (PC) who recently transferred from a high-crime London precinct to Fairhaven to escape an ex-boyfriend. Frustrated by fetching tea and fighting gender bias among her male superiors, she jumps at the chance to investigate a real murder when the retirees engineer a way to get her assigned to the case.

Ron is a strong-willed, vocal resident of Coopers Chase and a core member of the Thursday Murder Club. Known for his fighting spirit and history in union activism, he acts as the outspoken defender of the residents' rights. He often uses his brash personality as a distraction technique for the club's investigations.

Ibrahim is a retired psychiatrist who remains highly active and sharp-minded. He calculates logistics, analyzes human behavior, and occasionally still sees clients at Coopers Chase. He uses his understanding of psychology to help the club manipulate situations, carefully timing and staging interactions with the police.

Ian is the greedy, profit-driven majority owner of the Coopers Chase retirement village. He aggressively pushes a new development project called The Woodlands, which requires digging up a convent's cemetery. His absolute disregard for the residents' wishes and the church's sacred ground earns him numerous enemies early in the story.

Chris is a Detective Chief Inspector (DCI) assigned to the Coopers Chase murders. A single man trying to lose weight, he is initially dismissive of the retirees but eventually finds himself completely outmaneuvered by their meddling, forcing him to form an unorthodox working relationship with the Thursday Murder Club.

Tony is Ian Ventham's aggressive construction partner who owns a twenty-five percent stake in the Coopers Chase developments. He has a violent criminal history tied to drug dealing and past shootings. When Ian attempts to cut him out of the new development, Tony decides to take revenge, but his violent past catches up to him first.

Bogdan is a quiet, efficient contractor hired by Ian to handle construction and security around Coopers Chase. He approaches life and death with a pragmatic attitude and frequently crosses paths with the retirees, forming a surprising bond with Elizabeth when his excavation uncovers complications in the cemetery.

Matthew is a priest who arrives in town to stop Ian from digging up the Garden of Eternal Rest. He claims a moral obligation to protect the nuns buried there and promises to make the development as difficult as possible, though his intense dedication to the site hints at deeper personal ties.

Jason is Ron's son, a former boxing champion who now makes a living off television appearances and his past fame. He harbors a troubled history and becomes a prime suspect when police find an old photograph of him at the scene of the first murder, forcing him to rely on his father's friends for help.

Karen is an IT database administrator for a secondary school and the daughter of Gordon Playfair, who owns the farmland adjoining Coopers Chase. She rejects Ian's aggressive attempts to buy their property, prioritizing her father's happiness and peace over a massive financial payout.

Penny is a retired police detective inspector and the original co-founder of the Thursday Murder Club alongside Elizabeth. She currently resides in a coma at the on-site nursing home, where her husband and Elizabeth visit her daily to recount cold cases and update her on the current investigation.

John is a retired veterinarian and Penny's deeply devoted husband. He spends almost all of his time sitting by his comatose wife's bedside at the Willows nursing facility, presenting himself as a quiet, grief-stricken spouse who listens passively while Elizabeth discusses murder cases.

Bernard is a quiet widower at Coopers Chase who spends his days sitting near the Garden of Eternal Rest, mourning his late wife. He forms a gentle, supportive connection with Joyce through daily check-in calls, though he harbors intense private guilt.

Joanna is Joyce's successful daughter. She initially views her mother's life at the retirement village as mundane and assumes Joyce needs looking after, but she grows surprised and impressed by her mother's newfound adventurous streak and investigative work.

Stephen is Elizabeth's third husband, a gentle man living with her at the retirement community. He is highly observant and forms a quiet friendship with Bogdan over regular games of chess in their home.